Powered By Blogger

Site Meter

About Me

My photo
Auckland, North Island, New Zealand
Wine tour operator, wine writer and lapsed physiotherapist. "Nature abhors a vacuum. I personally hate dusting."

Followers

Wednesday, January 20, 2010

Screw Cap Vs Cork



(We all need closure)


By Phil Parker, wine writer and operator of Auckland Fine Wine Tours Ltd.


Like most wine drinkers, you are no doubt aware of the increasing trend for our wines to be sealed with a metal screw cap.

New Zealand in particular is leading the way, with something like 90% of our wines under screw cap and that percentage likely to steadily increase. Some of our top producers, e.g. Kumeu River, have totally abandoned the traditional cork closure in favour of screw cap (commonly referred to as the Stelvin).
Ironically it was the French who perfected the Stelvin closure and gave it its name: Stel = steel, vin =wine.

Why screw cap? Is it cheaper? Surely the wine won’t last long? Yadda yadda …

The paramount reason for the move away from cork is the problem of cork taint (or ‘corked’ wine). This is caused by a chemical known as TCA (trichloroanisole), which in tiny amounts – a few parts per trillion – will give wine the mouldy odour and flavour of rotting damp cardboard, and destroy the fruit characters.

TCA occurs naturally in a mould which affects cork trees. For whatever reason, the cork growers in Spain and Portugal had been sending us increasing numbers of dud corks. In excess of one in ten bottles of wine was affected.

Unfortunately, especially in the USA, screw caps are associated with cheap ‘jug wines’ and face an image problem. But even there, some of their top producers have switched to Stelvin and there is a growing awareness that it’s not a bad thing. Initial resistance by consumers has given way and there is a groundswell of favourable opinion.

Are screw caps cheaper than corks? Yes, slightly, but the cost of converting from a cork bottling line to screw cap is a significant investment for the winery.

Will the wine last as long? Experience with screw caps doesn’t go much further than 15 years, but indications are that the perfect airtight seal ensures that fruit flavours are preserved for a much longer period. But the wines will still age and change characters over time. The theory that the cork allows the wine to ‘breathe’ is a myth – the chemical reductive ageing processes within a wine will still take place without the need for oxidation.

Can a wine still be ‘off’ even when under Stelvin? Yes, nothing’s perfect. It can happen but very, very rarely. There is a potential problem of sulphite formation in wines, leading to a bad egg/cabbage aroma. This can be eliminated with careful winemaking techniques.

Can I store them upright? Yes, definitely. The only reason wines with corks are stored on their sides is to keep the cork damp and swollen to ensure a tight fit.

What about plastic corks? They are only good for drink straight away wines. They leak, the give the wine a plastic flavour, they are nigh on impossible to remove with a cork screw when you’re squiffy.

What about the romance of pulling the cork? If that’s where you get your romance, maybe you should get out more often.



No comments:

Post a Comment